Tooth-brush.



C. E. THOMPS ON.

TOOTH BRUSH.

APPLICATION FILED OCT. 19, 1915.

'1,Q09,51 6. Patented Dc. 19,1916.

i sas CHARLES E. THOMPSON, OF TROY, NEW YORK, ASSIGNOR OF ONE-HALF TO FRANCIS H.

' WAGER, OF TROY, NEW YORK.

TOOTH-BRUSH.

Specification of Letters Patent.

PatentedlDec. is, rare.

Application filed October 19, 1915. Serial No. 56,671.

county of Rensselaer and State of New York,

have invented certain new and useful Improvements in Tooth-Brushes, of which the following is a specification.

My invention relates to tooth brushes, and the object of my invention is to provide a tooth brush made up of short, strong, elastic, projecting prongs which will be eflicacious, pleasant and durable in use; together with such other elements and combinations as are hereinafter more particularly set forth and claimed.

I accomplish these objects by means of the mechanism illustrated in the accompany ing drawing, in which:

Figure 1 is a plan view partly in section. Fig. 2 is a longitudinal section along the lines, 11, on Fig. 1. Fig. 3 is a perspective view with a part of the handle broken away.

Similar letters refer to similar parts throughout the several views.

' On a suitable handle, A, I place a tube, B, which tube is closed at one end, 0, provided with a contracted portion, D, at the other end which is open and into which the supporting end of the handle, A, may be inserted, as shown in Figs. 1 and 2. I make the inner side, 6, of the tube, B, parallel with with the other walls surrounding the cavity lengthwise, but concave on its outside or face from which the prongs, E, project. There will thus be secured a graduated in crease of thickness of rubber in the body face from thecenter of the brush lengthwise toward eachend with a maximum thickness at the ends. This is clearly seen in Fig. 2.

I construct the prongs, E, relatively large at the bottom and coming to a point or edge at the top, preferably wedge or chiselshaped, so that the diameter of the base portion shall be approximately half the length of the prongs. It is important to avoid too great length of prong, since by increasing the pivoting arc of each prong, just somuch reduces the friction produced by the general movement of the brush, and it is friction alone that cleanses the teeth and gums during the process of brushing. Prongs in. long will pivot in. each way without friction. If, therefore, there is a l-in. stroke the friction stroke is only a in., and if, as frequently happens, the tooth brush stroke is only in., there is no friction stroke at all. This has been shown to be afact. The 9; in. prong under the same conditions would have a play each way of in., which theoretically would cause only in. loss of friction, but in reality it would be less, since the farther the prong extends from the back of the brush, the more readily it bends under pressure. The prongs should be, when made of rubber or similar material, about or approximately 1} in. in length. They should be wedge, or chisel shaped and at the base they should be about 2; in. in diameter. When they are made as heretofore constructed long and conically-shaped truncated prongs-they bend, as before stated, without giving sufiicient friction in the stroke of the brush through the mouth; they will not enter between the teeth and dislodge the particles and are very ineffectual in operation. A perfect cone-shaped prong is preferable toa truncated-cone form, or a bluntended slightly tapering prong, but a wedgeshaped prong is the most eflicient form of all.

In order to have the particles which have become lodged between the teeth removed, it is necessary that the prongs should be inserted between the teeth. To do this they must be of such form as will permit them to enter the cavities or interstices, and they must also have stiffness which will cause them to project therein.

When. I have used the term rubber, I mean toinclude any similar pliable material.

The principle of construction in the formation of a rubber tooth brush, for which I contend and for which I ask the protection of United States Letters Patent, is that of a body with prongs integral thereof, having fix a practical efiicient mean between stiffof acute angle, triangular, prism-shaped prongs arranged in rows runnin lengthwise of the body thereof, and havlng their fiat, tapering sides set transversely thereto.

2. A tooth brush comprising a handle; a rubber tube having at one end a restricted neck, one of the Walls of the cavity through the tube straight and parallel to the axis of the tube on the inner side and concave on the outer side; and a series of prongs on the said concave surface of the tube, said prongs sharpened at one end and differing in diameter gradually from their base to the sharpened end, substantially as described.

3. A rubber tooth brush having a longitudinal cavity in its body adapted to receive the end of a supporting handle and having one of the Walls of the cavity straight parallel to the axis of the tubular body on its inner side and concave on its outer side,,said concave side having a series of wedge-shaped prongs. projecting therefrom, substantially as described.

4. A hollow-bodied rubber tooth brush having Wedge-shaped prongs integral with the body thereof and projecting from a concaved face, having its inner surface a plane parallel with the upper or opposite wall of {)he chamber, or hollow interior of the brush ody.

5. A rubber tooth brush having a longitudinal chamber in its body, and provided With two or more rows of acute angle, triangular, prism-shaped prongs running lengthwise, with their flat sides set crosswise of, and projecting from one side of the brush body and being integral therewith, combined with a handle having its supporting end inserted in the chamber in the brush body.

,In testimony whereof I have affixed my signature in presence of two witnesses.

CHARLES E. THOMPSON. Witnesses:

BEULAH CABLE, FREDERICK W. CAMERON. 

